Fix TextArea cursor being visible before it has focus for first time (#4128)

* Fix TextArea cursor being visible before it has focus

* Ensure cursor blink reactive can be toggled when the widget does and does not have focus, and responds correctly

* Update the CHANGELOG

* Update snapshots

* Update command palette snapshot

Author: darrenburns

CHANGELOG.md

@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Fixed a crash in the TextArea when performing a backward replace https://github.com/Textualize/textual/pull/4126
 - Fixed selection not updating correctly when pasting while there's a non-zero selection https://github.com/Textualize/textual/pull/4126
 - Breaking change: `TextArea` will not use `Escape` to shift focus if the `tab_behaviour` is the default https://github.com/Textualize/textual/issues/4110
+- `TextArea` cursor will now be invisible before first focus https://github.com/Textualize/textual/pull/4128
+- Fix toggling `TextArea.cursor_blink` reactive when widget does not have focus https://github.com/Textualize/textual/pull/4128
 
 ### Added
 

src/textual/widgets/_text_area.py

@@ -295,7 +295,7 @@ class TextArea(ScrollView, can_focus=True):
     soft_wrap: Reactive[bool] = reactive(True, init=False)
     """True if text should soft wrap."""
 
-    _cursor_visible: Reactive[bool] = reactive(True, repaint=False, init=False)
+    _cursor_visible: Reactive[bool] = reactive(False, repaint=False, init=False)
     """Indicates where the cursor is in the blink cycle. If it's currently
     not visible due to blinking, this is False."""
 
@@ -518,9 +518,13 @@ def _build_highlight_map(self) -> None:
                 # Add the last line of the node range
                 highlights[node_end_row].append((0, node_end_column, highlight_name))
 
-    def watch_has_focus(self, value: bool) -> None:
-        self._cursor_visible = value
-        super().watch_has_focus(value)
+    def _watch_has_focus(self, focus: bool) -> None:
+        self._cursor_visible = focus
+        if focus:
+            self._restart_blink()
+            self.app.cursor_position = self.cursor_screen_offset
+        else:
+            self._pause_blink(visible=False)
 
     def _watch_selection(
         self, previous_selection: Selection, selection: Selection
@@ -549,6 +553,14 @@ def _watch_selection(
         if previous_selection != selection:
             self.post_message(self.SelectionChanged(selection, self))
 
+    def _watch_cursor_blink(self, blink: bool) -> None:
+        if not self.is_mounted:
+            return None
+        if blink and self.has_focus:
+            self._restart_blink()
+        else:
+            self._pause_blink(visible=self.has_focus)
+
     def _recompute_cursor_offset(self):
         """Recompute the (x, y) coordinate of the cursor in the wrapped document."""
         self._cursor_offset = self.wrapped_document.location_to_offset(
@@ -1028,8 +1040,10 @@ def render_line(self, widget_y: int) -> Strip:
         )
 
         if cursor_row == line_index:
-            draw_cursor = not self.cursor_blink or (
-                self.cursor_blink and self._cursor_visible
+            draw_cursor = (
+                self.has_focus
+                and not self.cursor_blink
+                or (self.cursor_blink and self._cursor_visible)
             )
             if draw_matched_brackets:
                 matching_bracket_style = theme.bracket_matching_style if theme else None
@@ -1290,13 +1304,6 @@ def _on_mount(self, _: events.Mount) -> None:
             pause=not (self.cursor_blink and self.has_focus),
         )
 
-    def _on_blur(self, _: events.Blur) -> None:
-        self._pause_blink(visible=True)
-
-    def _on_focus(self, _: events.Focus) -> None:
-        self._restart_blink()
-        self.app.cursor_position = self.cursor_screen_offset
-
     def _toggle_cursor_blink_visible(self) -> None:
         """Toggle visibility of the cursor for the purposes of 'cursor blink'."""
         self._cursor_visible = not self._cursor_visible